20C;h26-h32
l(1)20Ca << bk1 << l(1)20Cb << bb << bk2 << l(1)carot3
Df(2R)Su(z)2-1.b8 suppresses meiotic drive of the Y chromosome in Df(1)X-1 males compared to controls.
Males carrying Df(1)X-1 /Dp(1;Y)BarSYy+ show three effects; progeny yield is reduced, X-Y non-disjunction is high, and reciprocal meiotic products are recovered unequally.
The frequency of X-Y nondisjunction seen in Df(1)X-1/Dp(1;Y)BarSYy+ males is increased by bbr10Δ3.1A-2, bbr10Δ3 and bbt13.2, but is not altered by bbr10Δ3.1A-1 or bbr12.
Fertile when in combination with Dp(1;Y)BarSYy+and sterile in combination with Dp(1;Y)y+mal126 or Dp(1;Y)mal+.
Heterozygotes with Dp(1;Y)BarSYy+ are fertile, weakly fertile with Dp(1;Y)y+mal126 and sterile with Dp(1;Y)y+mal+.
Df(1)X-1 males show a slight increase (<3-fold) in second-chromosome nondisjunction and a large (>700 fold) increase in XY nondisjunction. Unlike wild-type cells, XY nondisjunction is independent of the frequency of sex chromosome nondisjunction in Df(1)X-1 cells. Nondisjunctional second chromosome pairs are as likely to be at the pole opposite the X chromosome or that opposite the Y chromosome in Df(1)X-1 mutants, while they are more likely to be opposite the Y in wild-type cells. Likewise, nondisjoined XY and nondisjoined second chromosomes segregate independently from one another in Df(1)X-1 cells. Df(1)X-1 cells have a similar meiotic drive to wild type. Df(1)X-1 males are sick and not fully fertile.
Homozygous females and hemizygous males are not viable.
male viable with BSYy+ fertile with BSYy+ male viable with Dp(1;Y)y+mal+. male sterile with Dp(1;Y)y+mal+.
Heterozygote males are inviable due to the proximal X euchromatin deletion.
Deletion breakpoints are distal to or within l(1)20Cb and proximal to the nucleolus organiser.
Deficient for most of the basal X heterochromatin including bb and some proximal euchromatic loci.
Left limit of break 1 from non-inclusion of l(1)20Ca (FBrf0020833) Right limit of break 1 from inclusion of l(1)20Cb (FBrf0034331) Left limit of break 2 from inclusion of ABO-X (FBrf0076047) Right limit of break 2 from polytene analysis (citation unavailable)